Geranium Houseplant Care

Planting

• Choose a planter or container that is large enough for the geranium and that provides drainage. A 10- to 12-inch-diameter pot that is similar in depth holds enough soil for the geranium roots. The container must have at least one bottom drainage hole, otherwise the excessive moisture collects in the bottom of the pot. Geraniums tolerate a range of soil types. In containers, a well-drained potting mixture that's rich in organic matter works well. Most suitable commercial mixes contain soil, peat and vermiculite or perlite. Plant the geranium in the potting soil at the same depth it was growing at in its nursery container or the garden bed, if you are digging up outdoor plants to bring them inside.

Climate Requirements

• Keep indoor geraniums in an area that receives bright sunlight at all times. South-facing windows typically supply the desired amount of sunlight unless outdoor trees or structures block the sun. Geraniums won't bloom well if they aren't supplied with enough light. During the short, cloudy days of winter, supplement sunlight with indoor artificial light. Place the geranium beneath a fluorescent grow light fixture for 16 hours a day to supplement the sunlight the plant does receive. Keep the plant in an area where temperatures remain between 65 and 70 degrees Fahrenheit at all times.

Water and Fertilization

• Allow the soil in the pot to dry slightly between each watering, but don't allow it to dry out completely. Geraniums need irrigation when the top 4 inches of soil begins to feel dry. Water the soil near the base of the geranium plant but avoid wetting the foliage. Plants with wet leaves are more likely to suffer fungal problems. Stop watering when the excess begins to drip out the bottom drainage hole. Light fertilization helps the geranium remain healthy and attractive. Combine a soluble fertilizer formulated for flowering plants with the irrigation water every two months from spring through fall. Apply the fertilizer when you irrigate, following the application amount on the fertilizer label.

Winter Care

• The varieties of geraniums grown as houseplants don't tolerate winter frost. You can keep the pots outdoors in a warm, sunny location during the summer, if desired, but you must bring them indoors before winter cold. Plants may die back slightly as they adjust to indoor light and growing conditions, but bounce back by spring if given proper light and water. Pinching back the top of each stem to the topmost bud in spring as new growth begins helps the geranium produce full growth and prevents legginess.